- #1
Ryansf98
- 15
- 0
Homework Statement
f(x) = Log(cosh(x-1)), find f'(x).
Homework Equations
The Attempt at a Solution
f'(x) = [1/cosh(x) - 1] * d/dx [cosh(x) - 1], => f'(x) = sinh(x) / [cosh(x) - 1]
Although, my marking scheme says the answer should instead be; cosh(x) + 1 / sinh(x).
Can someone explain where I'm going wrong? Thanks.